Context. The hot plasma in a galaxy cluster is expected to be heated to high temperatures through shocks and adiabatic compression. The thermodynamical properties of the gas encode information on the processes leading to the thermalization of the gas in the cluster's potential well and on non-gravitational processes such as gas cooling, AGN feedback, shocks, turbulence, bulk motions, cosmic rays and magnetic field. Aims. In this work we present the radial profiles of the thermodynamic properties of the intracluster medium (ICM) out to the virial radius for a sample of 12 galaxy clusters selected from the Planck all-sky survey. We determine the universal profiles of gas density, temperature, pressure, and entropy over more than two decades in radius, from 0.01R 500 to 2 R 500 . Methods. We exploited X-ray information from XMM-Newton and Sunyaev-Zel'dovich constraints from Planck to recover thermodynamic properties out to 2R 500 . We provide average functional forms for the radial dependence of the main quantities and quantify the slope and intrinsic scatter of the population as a function of radius. Results. We find that gas density and pressure profiles steepen steadily with radius, in excellent agreement with previous observational results. Entropy profiles beyond R 500 closely follow the predictions for the gravitational collapse of structures. The scatter in all thermodynamical quantities reaches a minimum in the range [0.2 − 0.8]R 500 and increases outward. Somewhat surprisingly, we find that pressure is substantially more scattered than temperature and density. Conclusions. Our results indicate that once accreting substructures are properly excised, the properties of the ICM beyond the cooling region (R > 0.3R 500 ) follow remarkably well the predictions of simple gravitational collapse and require few non-gravitational corrections.

Aims. We present the reconstruction of hydrostatic mass profiles in 13 X-ray luminous galaxy clusters that have been mapped in their X-ray and Sunyaev-Zeldovich (SZ) signals out to R200 for the XMM-Newton Cluster Outskirts Project (X-COP). Methods. Using profiles of the gas temperature, density, and pressure that have been spatially resolved out to median values of 0.9R500, 1.8R500, and 2.3R500, respectively, we are able to recover the hydrostatic gravitating mass profile with several methods and using different mass models. Results. The hydrostatic masses are recovered with a relative (statistical) median error of 3 % at R500 and 6% at R200. By using several different methods to solve the equation of the hydrostatic equilibrium, we evaluate some of the systematic uncertainties to be of the order of 5% at both R500 and R200. A Navarro-Frenk-White profile provides the best-fit in 9 cases out of 13; the remaining 4 cases do not show a statistically significant tension with it. The distribution of the mass concentration follows the correlations with the total mass predicted from numerical simulations with a scatter of 0.18 dex, with an intrinsic scatter on the hydrostatic masses of 0.15 dex. We compare them with the estimates of the total gravitational mass obtained through X-ray scaling relations applied to YX , gas fraction, and YSZ , and from weak lensing and galaxy dynamics techniques, and measure a substantial agreement with the results from scaling laws, from WL at both R500 and R200 (with differences below 15%), from cluster velocity dispersions. Instead, we find a significant tension with the caustic masses that tend to underestimate the hydrostatic masses by 40% at R200. We also compare these measurements with predictions from alternative models to the cold dark matter, like the emergent gravity and MOND scenarios, confirming that the latter underestimates hydrostatic masses by 40% at R1000, with a decreasing tension as the radius increases, and reaches ∼15% at R200, whereas the former reproduces M500 within 10%, but overestimates M200 by about 20%. Conclusions. The unprecedented accuracy of these hydrostatic mass profiles out to R200 allows us to assess the level of systematic errors in the hydrostatic mass reconstruction method, to evaluate the intrinsic scatter in the NFW c − M relation, and to robustly quantify differences among different mass models, different mass proxies, and different gravity scenarios.

Galaxy clusters are the endpoints of structure formation and are continuously growing through the merging and accretion of smaller structures. Numerical simulations predict that a fraction of their energy content is not yet thermalized, mainly in the form of kinetic motions (turbulence, bulk motions). Measuring the level of non-thermal pressure support is necessary to understand the processes leading to the virialization of the gas within the potential well of the main halo and to calibrate the biases in hydrostatic mass estimates. We present high-quality measurements of hydrostatic masses and intracluster gas fraction out to the virial radius for a sample of 13 nearby clusters with available XMM-Newton and Planck data. We compare our hydrostatic gas fractions with the expected universal gas fraction to constrain the level of non-thermal pressure support. We find that hydrostatic masses require little correction and infer a median non-thermal pressure fraction of ∼ 6% and ∼ 10% at R 500 and R 200 , respectively. Our values are lower than the expectations of hydrodynamical simulations, possibly implying a faster thermalization of the gas. If instead we use the mass calibration adopted by the Planck team, we find that the gas fraction of massive local systems implies a mass bias 1 − b = 0.85 ± 0.05 for SZ-derived masses, with some evidence for a mass-dependent bias. Conversely, the high bias required to match Planck CMB and cluster count cosmology is excluded by the data at high significance, unless the most massive halos are missing a substantial fraction of their baryons.